Help! One more time...roadster 1.5 battery question

[djp]

Balancing looks good! Your bricks are all within 1% of 95% SOC, which is perfect for a Range charge. The CAC is recalculated after a Standard or Range charge completes. It may take a couple of deep discharges to recalibrate it.

 

[Roadrunner13]

Balancing looks good! Your bricks are all within 1% of 95% SOC, which is perfect for a Range charge. The CAC is recalculated after a Standard or Range charge completes. It may take a couple of deep discharges to recalibrate it.

So here we go, one deep discharge today!
Thx!

 

[Roadrunner13]

Balancing looks good! Your bricks are all within 1% of 95% SOC, which is perfect for a Range charge. The CAC is recalculated after a Standard or Range charge completes. It may take a couple of deep discharges to recalibrate it.

Allright, so this is disappointing.

I drove 285 km both days last weekend, with the long run of 250 km being the first drive of the day after a range charge on Saturday morning.
For the night or should I say 'evening', I charged on a super 240V 70A Sun Country Highway Charger!!!
REALLY NICE, 4 hours range charge topped off and balanced BEFORE I went to bed!!!

The second day, I couldn't start with the long drive and I ended driving 250 km in one shot but after two shorter drives.
Both days ended with the Range battery showing below 20% or Standard battery around 10%...with an optimistic 60 km to go.

Now to the sad part, the CAC continued to drop a little more during the week-end
and it ended up at the following value after doing a standard charge back at home Sunday(and Monday) on 110V.

with a somewhat not completely balanced pack...

After it completed charging to 98% Standard, the connector light went from Orange to Green and the balancing started...
and stopped after 10 mins in the following state (better than when it all started, but not as good as after the previous charge):

110V & Standard charge don't seem to play nice with the balancing algorithm...
So the electrician is called up and 220V charging is the near future for this roadster.

As I understand it, balancing occurs normally after standard charges on 220V, right? No need for Range charging then?

I'm still quite concerned after seeing the CAC drop from 156 to (now) 143 in my 3 months of driving!

 

[djp]

I'm still quite concerned after seeing the CAC drop from 156 to (now) 143 in my 3 months of driving!

How many kilometers do you have on the odometer? You can calculate an expected Standard Range from the Plug In America Roadster Battery Study:

Standard Range = 185.79 - 0.2854 * Mileage / 1000

(all numbers in miles)

http://www.pluginamerica.org/surveys/batteries/tesla-roadster/PIA-Roadster-Battery-Study.pdf

It's possible the higher CAC reading was overstated, and it's now catching up to the real value after a few long drives. None of your bricks look like outliers, which is good news.

Yes, the pack balances after both a Standard and Range charge.

 

[Roadrunner13]

How many kilometers do you have on the odometer? You can calculate an expected Standard Range from the Plug In America Roadster Battery Study:

Standard Range = 185.79 - 0.2854 * Mileage / 1000

(all numbers in miles)

http://www.pluginamerica.org/surveys/batteries/tesla-roadster/PIA-Roadster-Battery-Study.pdf

It's possible the higher CAC reading was overstated, and it's now catching up to the real value after a few long drives. None of your bricks look like outliers, which is good news.

Yes, the pack balances after both a Standard and Range charge.

I have 10818 miles on the odometer.
So the calculation would yield: 182,7 miles or 293 km... which is 10 km more than what I read this morning (283km) about 3%.
So it's not off by that much so far, that's the good news.

Looking at the study, a CAC of 143 is equivalent to a car with at least twice (if not three times) what mine has,
so I do hope more regular 220V balancing will stop the downward trend!

Thanks for the feedback!

 

[hcsharp]

...After it completed charging to 98% Standard, the connector light went from Orange to Green and the balancing started...
and stopped after 10 mins in the following state (better than when it all started, but not as good as after the previous charge):

View attachment 55774

I'm not sure I'm understanding you correctly. The above pic shows a battery that is still balancing. It hasn't stopped until the grid is all 0s.

I'm still quite concerned after seeing the CAC drop from 156 to (now) 143 in my 3 months of driving!

I think you have reason to be concerned. It shouldn't be dropping that fast. I've heard that charging on 110 doesn't do as good a job of keeping your pack balanced which might explain it, but that may not be correct about 110 charging. I hope it's OK.

 

[Roadrunner13]

I'm not sure I'm understanding you correctly. The above pic shows a battery that is still balancing. It hasn't stopped until the grid is all 0s.

Yes, unfortunately, that was the state of the grid when the charge/balancing stopped by itself.
That might be why 110V is not recommended, balancing doesn't complete on 'standard' charge.
Since then, I have not been able to be present when charging stopped.

I think you have reason to be concerned. It shouldn't be dropping that fast. I've heard that charging on 110 doesn't do as good a job of keeping your pack balanced which might explain it, but that may not be correct about 110 charging. I hope it's OK.

Well, the electrician is booked for the week of the 25.
So, hopefully I probably did one of my last 110V charge!
One important variable will be eliminated!
I'll have to take a couple more long rides/deep discharges and see what happens.

P.S. If it goes as planned, this will be a 70A roadster charger!

 

[hcsharp]

Yes, unfortunately, that was the state of the grid when the charge/balancing stopped by itself.

How do you know it had stopped balancing? If I saw that on the screen I would assume it was still balancing. Sometimes it will continue balancing for a couple hours after it stops charging.

Well, the electrician is booked for the week of the 25.
So, hopefully I probably did one of my last 110V charge!
One important variable will be eliminated!
I'll have to take a couple more long rides/deep discharges and see what happens.

P.S. If it goes as planned, this will be a 70A roadster charger!

Be careful - you might get some Roadster visitors!

 

[wiztecy]

I agree with Henry, you have to allow the grid to reach all 0's, can take 1/2 a day or longer if its really out of balance. I've also seen my pack balance fast one day then the next take a couple of hours.

 

[Roadrunner13]

How do you know it had stopped balancing? If I saw that on the screen I would assume it was still balancing. Sometimes it will continue balancing for a couple hours after it stops charging.

After the range charge, I had seen balancing for about an hour during which the grid very progressively became all 0s.
But what I learned is that while the balancing algorithm was doing its dance of 0s and 1s on the grid display,
the plug was glowing green for all the duration of balancing...

This last time, the plug glowed green for only 10-15 minutes before earing the contactors 'click-out' and the plug going dark with the grid still showing 1s as per the picture just beforehand.
Of course, after the plug shuts off, the grid jumps to show only 0s but I take this as the 'default' screen whether balancing is stopped or completed.
In this case, because the grid jump was 'abrupt' (3 columns of 1s to all 0s), I considered it stopped before completion.
That's my best educated guess at this point.

Be careful - you might get some Roadster visitors!

There are so few of us around here, that I'm in no danger of being overwhelmed and see my hydro bill go up for it.
I'd be more wary if I lived in LA!
So all are roadsters are welcome

 

[wiztecy]

The pack does not balance when charging and will still balance when the charge connector is pulled from the car. If you turn the key, balancing will stop balancing will not resume until after the next charge session.

 

[Roadrunner13]

The pack does not balance when charging and will still balance when the charge connector is pulled from the car. If you turn the key on the balancing will stop and will not resume until after the next charge session.

Right, I had missed that in your previous comment, sorry!
So the plug green glowing is NOT related...and I should be able to check the grid anytime after 82% SOC charge as long as the key is not turned on...
I'll try and check this when the car returns from the beauty salon, it's getting paint armour.